This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Perform true dynamic imaging in rodent lungs using spiral imaging using hyperpolarized gases, He and Xe. The goal is to understand the dynamics of the respiratory cycle, and perform only proton scans to optimize the imaging and timing parameters of the spiral sequence. The next goal is to extend these scans to demonstrate the capability of performing dynamic HP gas studies. These studies will impact future work in the Center for In Vivo Microscopy.